Tiltable axis attrition mill with hammer and knife rotor



R. B. RECORDS Sept. 24, 1957 TILTABLEI AXIS ATTRITION MILL WITH HAMMER AND KNIFE ROTOR Filed Aug. 1, 1955 2 Sheets-Sheet l INVENTOR. ion/2r A Esra/205 2,807,424 TILTABLE AXIS ATTRITION MILL WITH HAMMER AND KNIFE ROTOR Filed Aug. 1, 1955 Sept. 24, 1957 R. B. RECORDS 2 shgets sheet 2 R2,: 00 mm W; Z flw we W a 7 E i m i ited States TILTABLE AXIS ATTRITION MILL WITH HAMMER AND KNIFE ROTOR The present invention relates to a new and novel attrition mill which is especially adapted for use in refining various mineral ores.

It is a major objectof the present invention to provide an attrition mill which is capable of breaking down min eral ores to their individual component grains.

Another object is to provide an attrition mill wherein the fineness of attrition may be readily and accurately adjusted.

A further object of the invention is to provide an attrition mill which is simple of design and rugged of con- ;truction whereby it may afford a long and useful service Yet another object is to provide an attrition mill which is of more compact size and lower weight than heretoforeproposed mills of comparable capacity.

It is a further object to provide an attrition mill which may be operated by personshaving no particular skill or training.

An additional object is to provide an attrition mill of the aforedescribed nature which may be constructed, maintained and operated at less cost than heretoforeproposed mills of comparable capacity.

These and other objects and advantages of the present invention will become apparent from the following detailed description, when taken in conjunction with the appended drawings, wherein:

Figure 1 is a side elevational view of a preferred form of attrition mill embodying the present invention;

Figure 2 is a front elevational view of said attrition mill;

Figure 3 is a rear elevational view of said attrition mill;

Figure 4 is an enlarged vertical sectional view taken on lines 44 of Figure 2; and

Figure 5 is a vertical sectional view taken on lines 55 of Figure 4.

Referring to the drawings, the preferred form of attrition mill embodying the present invention broadly comprises a housing H formed with an ore-receiving intake I at its front end and with a discharge D for the refined ore at its rear end, grinding means G mounted within the housing H, a base B, and support means S interposed between the base and the housing. The support means S permits the housing H to be adjustably tilted between its solid and dotted outline positions of Figure 1, i. e. with its front end higher than its rear end. This tilting adjustment controls the time required for an increment of ore to pass through the housing H and thence the fineness of attrition of such ore.

More particularly, the housing H is shown as having a diamond-shaped transverse cross-section, and it includes side walls of equal length, a vertical front wall 12 and a vertical rear wall 14. The front wall 12. is formed with an intake opening 16 above the horizontal center-line of the housing. An intake chute 18 extends upwardly and forwardly from the opening 16. The rear wall 14 is formed with a discharge opening 20 below the horizontal center-line of the housing from which a discharge chute 22 extends downwardly and rearwardly. As shown in Figures 3 and 5, the rear wall 14 is also formed with an opening 24 at a point above the horizontal centerline of the housing for a purpose to be set forth hereinafter. The exterior of the front and rear walls 12 and 14. centrally mount front and rear bearing members 26 and 28, respectively, for supporting a shaft 30. This shaft carries a plurality of hammer members 32 and knife mem bers 34 that comprise the grinding means G which act upon the ore passing through the interior of the housing H.

Referring to Figures 4 and 5 for a detailed showing of the hammer members 32 and knife members 34, it will be observed that each hammer member includes a pair of aligned ring elements 36 that are keyed to closely ax ially spaced points on the shaft 30. These ring elements 36 are formed with a plurality of circumferentially-spaced and axially-aligned bores 38. Through each pair of aligned bores 38 is extended a pin element 40. Each of these pin elements 40 serve to pivotally interconnect the radially inner end of an arm element 42 to the ring elements 36. The radially outer end of each arm element 42 rigidly supports a weighted hammer element 44. The knife members 34 likewise include a plurality of aligned ring elements 46 which are keyed to the shaft 30 at closely axially spaced points. These ring elements 46 are formed with a plurality of circumferentially-spaced and axially-aligned bores &8. An axially extending bar 5%) is inserted through each set of aligned bores 48. These bars 59 serve to pivotally support the radially inner ends of a plurality of knife elements 52. These knife elements 52 may each consist of a flat, elongated piece of steel.

The base B includes a flat, horizontal base plate 54 upon which are rigidly mounted three upstanding identical and aligned pivot plates 55, 56 and 57. These pivot plates are each formed with a bore 58. These bores 58 are in horizontal alignment and serve to support a pivot bar 60 extended therethrough. The pivot bar 60 is received by a pair of aligned bores 62 formed at the lower end of a pair of generally triangular side plates 64 and 65 which rigidly depend from the opposite sides of the housing H so as to be disposed between pivot plates 56 and 57 of the base B. This arrangement permits the housing H to be tilted with its front end higher than its rear end between its solid and dotted outline positions of Figure 1. The actual tilting adjustment of the housing H relative to the base B is effected by means of a threaded crank arm 66 which is journaled at its lower end to a support 68 that is rigidly secured to one of the pivot plates 57 and which has its threaded portion '70 inserted through a nut element 72 that is rigidly afiixed to the side plate 65. It will be apparent that this arrangement will also serve to lock the housing at the desired angle relative to the base once such angle has been obtained.

The shaft 35 is rotated by means of an electric motor 74 which is rigidly supported upon a horizontal plate member 76 having one of its ends rigidly affixed to the side plate 64. The opposite end of this plate member 76 is secured to the upper end of a depending ear element 78. The ear element '78 is formed with a bore fit? that is received by the pivot bar 69. Hence, the electric motor 74 will undergo tilting in unison with the housing H. Rotation is transferred from the electric motor 74 to the shaft 3% by means of a first pulley 82 keyed to the shaft 84 of the electric motor, a second pulley 86 keyed to the front end of the shaft 3% and a belt 88.

In the operation of the aforedescribed device, ore to be ground is fed into the upper end of the intake chute 18 and passes through the interior of the housing and out of the discharge chute 22. As the ore moves through the length of the interior of the housing, it is ground between Patented Sept. as, 1957 i the hammer and knife elements 44 and 52, respectively, I

and the inner surfaces of the side walls 10. Such grinding motion effects attrition of the ore. For any given speed of the shaft 30 thetime required for the'ore. to pass through the interiorof the housing is controlled by the angle at which the housing H isadjhstedrlative to the base B. It is possible to controlthis timefand hence the fineness of attrition ,withinvery .closelimitsby means of the crank arm, 66., It may. be desirable in some instances to attach a vacuum connection 90v to the opening 24 in the rear wall 14.' The use of vacuum will not only protect the bearings 26. and 28 but it will also serve to collect the dust and, finer. particles of the ore from within the housing H. M a U It should be particularly noted that although the transverse cross-section of the housing H is shown as being diamend-shaped in the aforedescribed embodiment of the mill, other cross-sections may'be employed, as for example, a circle or asquare. Additionally, other forms of grinding means may be utilized in place of the particular hammer andknifemembers described hereinbefore. A mill embodying the present invention is particularly adaptable to the attrition of sandstones, limestones and other types of sedimentary rocks, and is capable of breaking these rocks down to their individual component grains. Its use is not limited to the attrition of these rocks,

however.

It will be apparent to those skilled in the art that various modifications and changes may be made with respect to theforegoing detailed description of what is presently considered to be the preferred embodiment of the present invention Without departing from the spirit of the invention or the scope of the following claims.

I claim:

1. An attrition mill, comprising: a housing formed with an intake at its front end and a discharge at its rear end; hammer and knife members disposed Within said housing; a base; support means interposed between said base and .said housing, said support means permitting said housing to be adjustably tilted with its front end higher than its rear end so as to vary the fineness of attrition of material passing through said housing; and, means for locking said housing relative to said base.

2. An attrition mill, comprising: a housing formed with an intake at its front end and a discharge at its rear end; a shaft extending through said housing from the front to the rear thereof; grinding means carried by said shaft; a motor coupled to said shaft; a base; support means interposed between said base and said housing and motor, said support means permitting said housing and said motor to be concurrently adjustably tilted with their front ends higher than their rear ends so as to vary the fineness of attrition of material passing through said housing; and, means for locking said housing and said motor relative to said base.

3. An attrition mill, comprising: a housing formed with an intake at its front end and a discharge at its rear end; a pair of side plates extending vertically from said housing and formed with horizontally aligned bores; grinding means disposed within said housing; a base having a plurality of upstanding pivot plates formed with horizontally aligned bores; a pivot bar extending through said bores normal to the direction of flow of material through said housing so as to permit said housing to be adjustably tilted with its front end higher than its rear end so as to vary the fineness of attrition of material passing through said housing; and, an externally threaded crank arm having its lower end rotatably connected to said base and its threaded portion disposed within a nut element that is rigidly secured to said housing.

4. An attrition mill, comprising: a housing formed with an intake at its front end and a discharge at its rear endya pair of side plates extending vertically from said housing and formed with horizontally aligned bores; a shaft extending through said housing from the front to the rear thereof; a horizontal motor supporting plate hav ing one of its ends rigidly afiixed to one of said side plates and its other end connected to an car which is formed with a bore; a base having a plurality of upstanding pivot plates formed with horizontally aligned bores; a pivot bar extending through said bores normal to the direction of flow of material through said housing so as to permit said housing and motor to be adjustably tilted with their front ends higher than their rear ends so as to vary the fineness of attrition of material passing through said housing; and, means for locking said housing relative to said base.

References Cited in the file of this patent UNITED STATES PATENTS 64,834 Bruce May 21, 1867 213,471 Toofllin Mar. 18, 1879 1,161,859 Hardinge Nov. 30, 1915 1,450,289 Hardinge Apr. 3, 1923 1,517,538 Daman Dec. 2, 1924 1,933,764 Ruth Nov. 7, 1933 2,264,915 Meister Dec. 2, 1941 2,623,737 McEachran Dec. 30, 1952 

